Rolling support mechanism for pivoting bookcase or the like

ABSTRACT

A folding bookcase or other furniture or wall unit having a rolling mechanism guided along a floor track, the rolling mechanism supporting a substantial portion of the weight of the unit. One preferred construction includes a first wall section having first and second vertical lateral edges, the first vertical lateral edge being pivotally connected to a support, a second wall section having first and second vertical lateral edges, the first vertical lateral edge being pivotally connected to the second vertical lateral edge of the first wall section along a vertical axis therebetween; a floor track or guide; and a pivoting roller mechanism rotatable mounted at a bottom edge of the second wall section proximate the first vertical lateral edge of the second wall section for supporting a load the second wall section on the floor guide, wherein the pivoting roller mechanism includes one or more rollers, roller rotating about a horizontal axis and engaging the floor guide, wherein the rollers are constructed and arranged to have an effective rotational axis in line with the load applied from the second wall section. The preferred configuration for the roller is a V-groove wheel that mates with a V-shaped ridge of the floor track.

RELATED APPLICATION DATA

This application claims priority to provisional application 60/758,577 filed Jan. 11, 2006, hereby incorporated by reference.

BACKGROUND

The field of the present invention is directed to folding furniture or wall section such as pivoting bookcases or other types of furniture and rolling support mechanisms for supporting the bookcase that allow for pivoting operation.

Heretofore, there have been various attempts to construct a bookcase which in a first position is disposed flat against a wall, or across a doorway, and then in a second position, the bookcase folds, pivoting outwardly in the middle and sliding to one side of the opening, extending perpendicularly out from the wall.

Unlike closet doors, which employ essentially a sliding mechanism supported from the ceiling, the bulk and weight of heavy units such as a bookcase, particularly one loaded with objects, is too heavy to be supported solely from a top suspension mechanism. Thus the system includes a lower runner along which the lower section of the bookcase may slide. Various mechanisms have been proposed for providing this sliding support, but the present inventor has determined desirability for an improved support system that can handle the high loads of the bookcase.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front perspective view of a pivoting bookcase in an extended position against a wall.

FIG. 2 is a front perspective view of the bookcase of FIG. 1 in the folded position.

FIG. 3 is a front elevation view of the bookcase of FIG. 1 in a left folding configuration.

FIG. 4 is a side elevation view of the bookcase system of FIGS. 1-3.

FIG. 5 is a partial right bottom perspective view of the bookcase of FIG. 1.

FIG. 6 is a detailed view of the roller section of the bookcase of FIG. 3.

FIG. 7 is a perspective view of the wheel assembly of FIG. 6.

FIG. 8 is a perspective view of the wheel assembly of FIGS. 6-7 removed from the bookcase section.

FIG. 9 is a perspective view of a cross-section of FIG. 8.

FIG. 10 is a plan view of the cross-section of FIG. 9.

FIG. 11 is a cross-sectional view of FIG. 10 taken along line 11-11.

FIG. 12 is a detail of the spring assembly of the slider component of FIGS. 8-11.

FIG. 13 is a top plan view of the spring assembly of FIG. 12.

FIG. 14 is a detail of the pivot section of FIG. 3.

FIG. 15 is a bottom left perspective view of the pivot piece of FIG. 14.

FIG. 16 is a right top perspective view of the pivot section as in FIGS. 14-15 as removed from the bookcase section.

FIG. 17 is a cross-sectional view of the pivot and slide mechanism of FIG. 16.

FIG. 18 is a cross-section of FIG. 17 taken along line 18-18.

FIG. 19 is a top perspective view of the slider element of FIGS. 16-18.

FIG. 20 is a cross-section of FIG. 19 taken along line 20-20.

FIG. 21 is a detailed cross-section of the track element of FIGS. 7-8.

FIG. 22A is a perspective view of a pivot block of alternate construction.

FIG. 22B is a perspective view of the pivot block of FIG. 22A showing internal details.

FIG. 23 is a perspective view of a first alternative pivoting caster system.

FIG. 24 is a perspective view of a second alternative pivoting caster mechanism.

FIG. 25A is a side elevation view of the mechanism of FIG. 24 showing internal details.

FIG. 25B is a cross-sectional view of FIG. 24 taken along line 25B-25B.

FIGS. 26 and 27 illustrate a third alternative rolling caster of a single wheel construction.

FIGS. 28-29 illustrate a fourth alternative pivoting roller mechanism of a two-wheel design.

FIGS. 30-31 illustrate a fifth alternative embodiment of a rolling pivot mechanism with an alternate wheel design.

FIGS. 32-33 illustrate a sixth alternative pivoting roller support mechanism of a two-wheel design wherein the wheels ride within a floor slot.

FIGS. 34-35 illustrate a seventh alternative mechanism of another two-wheel design with slider posts engaged within a slide channel.

FIGS. 36-37 illustrate an eighth alternative design using a single wheel in line with slider posts all engaged within a floor guide channel.

FIG. 38 is a detail of the upper left pivot mechanism of the bookcase system of FIG. 3.

FIG. 39 is a detail of the upper right pivot and slide mechanism of the upper right portion of the bookcase mechanism of FIG. 3.

FIG. 40 is a perspective view of an upper portion of the bookcase system of FIG. 3 illustrating details of the upper support system.

FIG. 41 is a top left perspective view on an enlarged scale of the top left section of the upper support system of FIG. 40.

FIG. 42 is an exploded perspective view of the upper support system of FIG. 41.

FIG. 43 is a top right perspective view of the upper right section of the support system of FIG. 40 on an enlarged scale.

Additional aspects and advantages will be apparent from the following detailed description of preferred embodiments, which proceeds with reference to the accompanying drawings.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Preferred embodiments will now be described with reference to the drawings. To facilitate description, any element numeral representing an element in one figure will represent the same element in any figure. The preferred embodiments will describe a particular folding furniture or wall section unit in the form of a folding bookcase, but it will be appreciated that details of the bookcase may be applied in other forms of furniture, wall sections or the like.

FIGS. 1 and 2 illustrate a typical bookcase 10 that may incorporate the rolling support mechanism according to a preferred embodiment. FIG. 1 illustrates the bookcase 10 disposed in an extended position against the wall 5. The left and right sections 12, 14 are interconnected via a vertical hinge mechanism 16 (visible in FIG. 2) that allows the interconnected central portions of the left and right sections 12, 14 to pivot relative to each other and outwardly away from the wall 5, both sections then sliding to the right side of the opening 7 within the wall 5. The bottom of the bookcase 10 includes a bottom support mechanism, described below, that engages a floor guide 20 and an upper crown section.

FIGS. 3-21 illustrate a preferred configuration for a pivoting bookcase 10 and bottom support system for such a pivoting bookcase or other pivoting or sliding structure. It will be appreciated that the bottom support system will be applicable to any pivoting or sliding mechanism besides bookcases such as a cabinet, sliding door or swinging door, fire door, room divider, fold-out desk, cupboard, china hutch, or the like.

The bookcase 10 as illustrated in FIG. 3 is of the same construction as illustrated in FIGS. 1-2 only in the reverse configuration with the sections 12, 14 folding to the left rather than the right. The pivoting roller mechanism 60, details of which are described below with respect to FIG. 6 et seq., is illustrated in the right side of the figure at the outer lower corner of the far side section 14 of the bookcase 10. On the lower left side of FIG. 3 is illustrated the pivot mechanism 80, described in detail below with reference to FIG. 14 et seq., the pivot mechanism 80 being located at the lower left edge of the bookcase 10 at the corner of the pivoting section 12. The floor track 20 is as previously described and will be described in further detail below. It will be appreciated that the left and right bookcase sections are interchangeable, namely that the bookcase may be folded and slide to the right as illustrated in FIGS. 1-2 or the respective hardware, namely wheel assembly 60 and pivot assembly 80 may be interchanged such that the bookcase may fold and slide to the left which is the orientation illustrated in FIG. 3.

The upper wall section 30 includes a rear angle plate 32 having a plurality of horizontal slots for facilitating easy mounting to a wall. The details of the left and right upper slider sections are described in further detail below with respect to FIGS. 38-42 below.

As shown in the bottom perspective view of FIG. 5, the bookcase 10 includes left and right sections 12,14 with the pivot mechanism 80 underneath the corner of the pivoting bookcase section 12 and the wheeled slider/roller mechanism under the lower corner of the sliding bookcase section 14. Both the pivot mechanism 80 and the roller mechanism 60 engage the upper angled ridge of the slider track 20.

Details of the rolling support mechanism 60 will now be described with reference to FIGS. 6-13. The roller mechanism 60 includes the housing or enclosure 62 that is pivotably mounted to a frame support member 40 (shown in FIG. 8) via a post 64 secured to the frame member 40 via nut 66. The frame member 40 is preferably made of metal such as steel and is sized to fit within a cavity underneath the outer corner of the bookcase section 14. This support frame member 40 has a side lip or flange which extends beneath the side wall of the bookcase section 14 to provide for firm support and connection thereto. Though the frame support may be omitted and the wheel mechanism mounted directly bookcase, but the frame support may offer certain advantages such as better distributing the load and transferring the load up the side of the bookcase.

The rolling support mechanism 60 includes a caster wheel 70 pivotally or rotatably mounted to the housing 62 via shaft or post 68 secured to the housing via a cotter pin 69. The rotational axis 70 a of the wheel 70 is centered below the connection point to the frame member 40, i.e., in line with the pivot axis 61 of the rolling support mechanism (see, FIGS. 10-11), such that the weight from the bookcase is transferred directly and in line onto the wheel shaft 68. As shown in FIG. 6, the pivot axis 61 of the roller mechanism is in line (intersects perpendicularly) In a preferred configuration, the wheel 70 is a V-groove type wheel whereby the V-groove 71 has an internal angle Θ as best illustrated in FIGS. 9 and 11. The V-groove 71 is preferably about 90 degrees and mates with the V-shaped ridge 22 of the floor track 20. This mating connection between the V-groove 71 in the wheel 70 with the V-ridge 22 in the floor track 20 provides for secure directional sliding/rolling stability for the rolling mechanism 60 along the track 20.

As one would understand from maneuvering a shopping cart about a grocery store, a pivoting wheel has a tendency to remain upon a given line of travel. Such a tendency may tend to urge the wheel 70 to “jump the track” and disengage from the V-ridge 22 of the track 20. In order to maintain alignment of the wheel 70 along the track 20, the rolling mechanism 60 also includes a guide track mechanism. The housing 62 extends forwardly away from the wheel 70 and includes a slide block 72 which is urged downward by a spring mechanism 75 onto the V-ridge 22 of the track 20. The slide block 72 also includes a V-groove 73 (having an internal angle Θ similar to the wheel 70) which engages the V-ridge 22 of the track 20. The slide block 72 is retained within the channel 79 formed within a forward section of the wheel housing 62. The V-groove 73 in the slide block 72 engages the V-ridge 22 in the floor track 20 and serves to guide the rolling assembly 60 along the track 20. Since the slide block 72 is cantilevered forward of the wheel 70 (the wheel 70 being positioned along the pivot axis of the post 64), the sliding V-block maintains the direction of travel of the rolling mechanism 60 in alignment with the V-ridge 22 of the track 20.

The slide block 72 is preferably made of ultra high molecular weight plastic (UHMW) and may alternately be made of nylon, Teflon, bearing bronze (which is a bronze material impregnated with oil, for example SAE 660 or 640), or a coated material such as Teflon coated metal or plastic. The wheel 70 is preferably a mild steel or low carbon steel having an integral ball bearing construction but may be made from other suitable materials such as iron, stainless steel, plastics, or polyurethane depending upon the load requirements. Such V-groove wheels are available through the McMaster-Carr catalog. Various manufacturers can make a suitable wheel for a given application. Specific wheel design/selection will depend upon several factors such as load, cost, size and operating conditions (e.g. corrosive areas). A preferred wheel for the bookcase system 10 illustrated is slightly smaller diameter than a standard size wheel and would be available from suitable manufacturers such as Killian Casters and Wheels.

As best illustrated in FIGS. 9-13, the slide block 72 is urged by a spring mechanism 75 downward into contact with the V-ridge 22 of track 20. The spring mechanism may be any suitable mechanism and this embodiment includes a coil spring 76 to which are attached upper and lower plates 78, 77. In the illustrated embodiment, the spring mechanism is designed to exert a load of between 5 lbs and 10 lbs. The upper plate 78 is attached to the upper section of the wheel housing 62 via bolt holes 78 a, 78 b. The lower plate 77 is in turn attached to or otherwise in contact with the slide block 72.

The slide block 72 translates vertically, being retained within the channel 79 in the forward section of the housing 62. Other suitable configurations may be employed for retaining the slide block such as internal pins or posts (e.g. one post on either side of the spring 76), or even a single pin disposed within the spring 76.

The wheeled end of the bookcase 10 is provided with the wheel mechanism 60 as it is that end that must traverse much of the length of the track 20 during folding and unfolding operation. The other end of the case is relatively fixed during the folding and unfolding operations and need only pivot. Preferably a pivot block configuration 80 is employed at the pivot end, and details of a preferred pivot block assembly system 80 are disclosed in FIGS. 14-20. Pivot block assembly 80 includes a block 82 into which a post structure 84 is inserted as is described below. The post structure 84 is mounted to frame member 90. Frame member 90 is of the same configuration and thus is interchangeable with the frame member 40 on the other side of the bookcase.

The block 82 includes a V-groove 83 having an internal angle A (typically about 90° which corresponds to the angle φ of the V-ridge 22 in the floor track 20. The floor track 20 is preferably secured to the floor via suitable connection mechanism such as by screws or bolts connected into the floor along the length of the track. The block 82 is secured in a fixed position via four screws or bolts (not shown) passing through the holes 82 a, 82 b, 82 c, 82 d in the block 82 and then through holes 21 a, 21 b, 21 c, 21 d in the floor track 21. The post 84 carries and transfers a substantial portion of the weight of the bookcase onto the block and thereby to the floor. Materials of the post 84 and block 82 are selected to permit rotation therebetween to allow the desired pivoting of the left side of the bookcase.

In order to facilitate moving of the unit and aligning the post 84 into central opening 88 in the block 82 on the floor track, the post 84 includes an extension member 85 which slides along curved or angled guide surfaces 86 in the top of the block, thereby guiding the extension portion 85 radially inward and thus providing self-seating for the post 84 into a proper seating position within the block 82. When in position, the extension 85 nests within the central opening 88 within the block 82.

FIG. 21 illustrates an enlarged detail of the floor track 20. The floor track 20 includes the upwardly extending V-ridge 22 which is shown to have an angle φ. Each of the engaging angles, namely angle θ for the V-groove of the wheel 70, angle θ for the V-groove in the slide block 72, angle λ in the V-groove in the pivot block 82, and the angle φ in the V-ridge of the floor track 20, are about 90° but other angles may be desirable. For example, the steepness of the angle (i.e., less than 90°) may provide for more alignment force for the elements but potentially could be more of an impediment to user's crossing over the floor track either on foot or such as in a wheel chair. Other possible configurations may be used for the rolling/wheel pivoting mechanism. Preferably, the primary load from the bookcase or other object being supported is aligned with the rolling axis of the wheel or other rolling/sliding support.

Despite the heavy load anticipated by a typical bookcase configuration, the roller mechanism including the V-groove wheel 70 and cantilevered V-groove slide block 72 allow use of a V-ridge floor track with a relatively low raised/vertical dimension on the order of 0.5 inches. Such a low threshold may advantageously minimize tripping hazard.

The block 82 of the previous embodiment has a generally square or box-shaped configuration. When pivoting about the block 82, the frame member 90 must have sufficient clearance so as not to contact the block 82. As shown in FIGS. 17-18, the block 82 is entirely below the frame member 90. Alternately, the block 82 may nest within the frame member 90 Figs, but would need to be sufficiently spaced from the side walls 90 a, 90 b. FIGS. 22A-22B illustrate an alternate configuration for the block 82, the alternate block 282 having a more round or cylindrical shape. This round shape is preferred because it enables a closer fit of the block 282 when it is nested within the frame member 90 (i.e. closer to the side walls 90 a, 90 b). The block 282 is otherwise of similar configuration with a bottom V-groove 283 that engages to floor track guide 22. The block 282 includes an angled guide surface 286 for guiding the extension portion 85 radially inward toward the central opening 288 and thus providing self-seating for the post 84 into a proper seating position within the pivot block 282. The block 282 is secured in a fixed position via two screws or bolts (not shown) passing through the holes 282 a, 282 b in the block 282 and then through holes in the floor track 21.

FIG. 23 illustrates a first alternative embodiment 110 including a V-groove wheel 112 with a forwardly extending slide block 114. The wheel 112 is mounted to be disposed in line with the load point of the bookcase and thus in line with the pivot axis 61 of the wheel 112. The slide block 114 is supported by a curved leaf spring 116.

FIGS. 24, 25A, 25B illustrate a second alternative embodiment 120 also including a V-groove wheel 122 disposed with its rolling axis in line with the load point of the bookcase. A slide block mechanism 124 supported by an angled leaf spring 126 extending forwardly in front of the wheel 122.

FIGS. 26-27 illustrate a third alternative embodiment 130 comprised of a single V-groove wheel 132 having its rolling axis in line with the load point. FIG. 26 also illustrates an alternative floor track (usable in various other embodiments) where the V-ridge 134 is disposed within a slot 136 within the track system 135. If practical, the entire floor track 135 of this embodiment or other embodiments may be recessed into the floor to provide a more smooth contour relative to the floor surface. The single wheel design of embodiment 130 does not include a guide mechanism but may nonetheless be suitable for certain applications.

FIGS. 28-29 illustrate a fourth alternative embodiment 140 comprised of a dual V-groove wheel configuration. The assembly 140 includes first and second V-groove wheels 142, 144 spaced in line and apart for engaging the V-ridge track 148. By locating the rolling axis of each of the wheels 142,144 on opposite sides of the pivoting support post 146 (equally spaced therefrom), the load from the bookcase is in line with the effective rolling axis of the wheels 142, 144 in combination.

FIGS. 30-31 illustrate a fifth alternative embodiment 150 similar to the previous embodiment. The wheel assembly 150 includes first and second wheels 152, 154. These wheels comprise double flange wheels which engage a square ridge 156 either on the surface of the floor or as illustrated disposed within a track groove 158. As in the previous embodiment, the effective rolling axis of the wheels 152, 154 is, in combination, in line with the load being applied to the wheel assembly.

FIGS. 32-33 illustrate a sixth alternative embodiment 160 comprised of a pair of in line wheels 162,164. The wheels 162,164 extend into a notch or a groove 166 in a track 168 or within the floor itself. Similar to the previous multiple wheel embodiments, the effective rolling axis of the wheels 162, 164, is, in combination, in line with the load on the wheel assembly 160.

FIGS. 34-35 illustrate a seventh alternative embodiment 170 comprised of a pair of flat roller wheels 172, 174 disposed on a common shaft 175. The rolling axis of each of the wheels is in line with the load being applied to the wheel assembly 170. Forward and behind the wheel pair and in line with the groove track 176 are a pair of guideposts 177, 178 which are disposed within the groove track 176 for keeping the wheel assembly aligned with the track.

FIGS. 36-37 illustrate an eighth alternative embodiment 180 having a central wheel 182 which rides within the track groove 186. The rolling axis of the wheel 182 is in line with the load applied to the wheel assembly 180. One or more guide posts 187, 188, arranged in line with and on one or both sides of the wheel 182, are also disposed within the track groove 186.

FIGS. 38-43 illustrate various details of the upper support system 30 of the pivoting bookcase system of FIGS. 1-4. The rear angle bracket 32 includes slots 33 for facilitating fastening to a wall. Three extenders 34, 35, 36 are connected to the angle bracket 32 and extend outward for supporting the transverse bar 37. The end mechanisms 38, 39 on the left and right sections slide along a U-shaped channel 31 (visible in FIG. 43) within the transverse bar 37. When pivoting to the left, the post 39 slides within the channel 31 as the right section 14 slides to the left and the post 38 holding left section 12 is permitted to rotate as the section 12 pivots thereabout. FIG. 42 illustrates a preferred assembly and operation method of the end mechanisms 38, 39. To assemble, the post or pin 38 is inserted into the hole 34 b in extender 34. To access the hole 34 b, the flexure element 34 a is flexed away from the hole 34 b because it its at rest position, the flexure 34 a covers the hole 34 b. When inserted, the pin 38 a passes through a hole in the bar 37 and then through a bushing 38 c (the bushing 38 c is disposed within the U-shaped channel 31 of the bar 37) and then into retainer 38 within the left section 12. The head of the pin 38 a is larger than the hole 34 b so it does not pass therethrough. When the flexure 34 a is released, it return over the head of the pin 38 and act to retain the pin in place. Alternately, the pin 38 a may be held in place by a cotter pin 38 a. The bushing 38 c rides within the channel 31. The end mechanism 339 on the right side is of similar construction.

Though the present invention has been set forth in the form of its preferred embodiments, it is nevertheless intended that modifications to the disclosed systems and methods may be made without departing from inventive concepts set forth herein. 

1. A folding furniture or wall section unit, comprising a first wall section having first and second vertical lateral edges, the first vertical lateral edge being pivotally connected to a support; a second wall section having first and second vertical lateral edges, the first vertical lateral edge being pivotally connected to the second vertical lateral edge of the first wall section along a vertical axis therebetween; a floor guide; a pivoting roller mechanism rotatable mounted at a bottom edge of the second wall section proximate the second vertical lateral edge of the second wall section for supporting a load the second wall section on the floor guide, wherein the pivoting roller mechanism includes one or more wheels, each wheel rotating about a horizontal axis and engaging the floor guide, wherein the wheels are constructed and arranged to have an effective rotational axis in line with the load applied from the second wall section.
 2. A folding furniture or wall section unit according to claim 1 wherein the first and second wall sections comprise first and second bookcase sections.
 3. A folding furniture or wall section unit according to claim 2 wherein the pivoting roller mechanism comprises a single wheel having an axis of rotation in line with the load applied from the bookcase.
 4. A folding furniture or wall section unit according to claim 1 wherein the floor track comprises an upwardly extending V-shaped ridge, wherein pivoting roller mechanism comprises a V-groove type wheel that engages the V-shaped ridge of the floor track.
 5. A folding furniture or wall section unit according to claim 1 wherein the pivoting roller mechanism comprises a V-groove wheel having a rotational axis in line and perpendicular with the rotational axis of the roller mechanism.
 6. A folding furniture or wall section unit according to claim 5 wherein the floor track comprises an upwardly extending V-shaped ridge, wherein pivoting roller mechanism comprises a V-groove type wheel that engages the V-shaped ridge of the floor track.
 7. A folding furniture or wall section unit according to claim 5 wherein the roller mechanism further includes a guide mechanism connected to and cantilevered out from the wheel, the guide mechanism engaging the floor track and steering the wheel for keeping the wheel on the floor track.
 8. A folding furniture or wall section unit according to claim 7 wherein the guide mechanism comprises sliding block having a V-groove that engages the V-shaped ridge in the floor track.
 9. A folding furniture or wall section unit according to claim 8 wherein the sliding block is spring-loaded for maintaining engagement with the floor track.
 10. A folding bookcase comprising a first bookcase section having first and second vertical lateral edges, the first vertical lateral edge being pivotally connected to a support; a second bookcase section having first and second vertical lateral edges, the first vertical lateral edge being pivotally connected to the second vertical lateral edge of the first bookcase section along a vertical axis therebetween; a floor track having an upwardly protruding V-shaped ridge; a pivoting roller-mechanism rotatable mounted at a bottom portion of the second bookcase section proximate the second vertical lateral edge of the second bookcase section for supporting a load the second bookcase section on the floor track, wherein the pivoting roller mechanism includes a V-groove wheel, wherein the V-groove wheel is constructed and arranged to engage the V-shaped ridge of the floor track. 